Shane McCatty, who was assistant manager of the league champion Unicorns in 2016, will manage the new team. The 25-man rosters of each team, made up of players 18-25 years old, will be stocked via scouting and from tryouts set for April 26-29 at the stadium.

USPBL founder Andy Appleby, the longtime Rochester sports entrepreneur who invested $16 million to build the stadium and launch the league in 2016, explained in a statement the impetus behind the new team's name.

"There have been numerous mastodons found in Michigan over the last 100 years, and I always thought 'Mastodons' had great potential as a sports team name. 'Woolly Mammoth' was better, although one had not been discovered here," he said. "Then, in 2015, a mammoth, complete with huge tusks, was unearthed on a farm in Chelsea, Mich., and our inspiration was complete. In addition to being distinctive, the 'Woolly Mammoths' name also allows for a whole host of fun marketing and merchandising opportunities. We are absolutely thrilled with the results."

The Woolly Mammoths' base colors are dark and light blue with red accents. The logo and designs are from Keego Harbor-based Martin Sports Productions.

At some point, the team will wear an alternate uniform of orange with animal prints — a Fred Flintstone look. The league sells merchandise for all of its teams at the ballpark and online.

The USPBL's 2017 season is scheduled to run May 11-Sept. 10. Games are Thursday through Sundays.

Appleby's goal is to get USPBL players to Major League Baseball, which would accomplish his business objective of legitimizing his league to the pro baseball world. He's part of the way there thanks to getting nine of his players signed to MLB farm teams. The league has its own finishing school and system for developing ballplayers, and major league scouts attended games last season.

Adding the Woolly Mammoths represents the first step in Appleby's expansion plan. His goal is to eventually build more stadiums in cities elsewhere in the Midwest, and has previously told Crain's that he hopes to have an agreement in place for a new ballpark in the next three to six months. Ground-breaking would be shortly after that. The stadium and new teams would be in place for summer 2018, he said.

Jimmy John's Field is along M-59 in Utica. The league averaged 3,200 per game, and sold out 42 of 75 games this season. Each team plays 75 games.

Actual woolly mammoths — known formally by their Latin name mammuthus primigenius — existed beginning in the Pleistocene epoch, or the Ice Age, beginning about 4.5 million years ago. They coexisted with early humans in Europe, northern Asia, and upper North America — including Michigan. The last known woolly mammoths died out about 2,000 BC on Wrangel Island in the Arctic Ocean.